With the advent of the so-called leisure society and the concurrent trend towards outdoor activities, recreational facilities are being elaborated in areas where water is available. Such recreational facilities typically require docks and marinas so that boats can be used conveniently. Also, recreational crafts such as pontoon boats are becoming increasingly popular.
In constructing marinas or small boats harbors, it is typically desirable to use a floating wharf structure which is accessible from land and has one or more fingers extending out into the body of water. The floating platforms used for building marinas are sometimes also used with some modifications as diving platforms and the like.
Generally, floating platforms include an upper decking material supported by a series of transverse and longitudinal support members. Similarly, pontoon boats typically include a deck disposed over two lateral elongated pontoons. This type of construction may also be used with modifications in larger watercrafts such as ferries, scientific research vessels and the like where the stability of the craft in the water is important.
Various types of floating components have been used or proposed in the prior art for the construction of rafts, floating docks and other water buoyant structures. One particularly popular type of buoyant or floating component has been the empty barrel or drum. While the use of such barrels typically made out of steel or the like has been a useful expedient, this practice nevertheless suffers from numerous drawbacks.
Docks and other floating structures made with steel barrels are relatively heavy and quite difficult to put in and take out, of the water. Also, the steel of the barrels tends to rust and specially designed brackets are often needed to secure the barrels to the framework of the dock or raft.
Furthermore, the type of framework required with barrels is typically of a sizeable and expensive nature. Still furthermore, the decking is often supported at a greater height above the water than is desirable.
Foam-filled automobile tires have also been used as water-buoyant components. Although somewhat useful and providing for the recycling of used tires, they also suffer from numerous drawbacks, including the fact that they are relatively heavy.
They are also considered to be expensive relative to the amount of floatation capacity they provide. Rigid foam made out of expanded polystyrene or the like have also been used with limited success since the latter has a tendency to deteriorate over time and to flake off or break up into small particles. They further have a tendency to absorb water.
Another type of floating component commonly used for docks, rafts, pontoon boats and other floating structures is the so-called modular float or “pontoon”. Such pontoons are typically divided into two types, namely those that are integral and have a hollow closed shell and those that are not integral and rely upon a closed-cell foam to provide the required positive buoyancy.
Upon installation in water, floating components such as pontoons must typically provide the ability to withstand the natural abuse of the environment such as moisture, exposure to gasoline and oils present in the water of a marina and weather conditions. The floating components must also have the ability to provide long term durability and easy maintenance and to be rodent- and crab-protected. Although most conventional prior art pontoons operate satisfactorily for the purpose intended, they nevertheless suffer from numerous drawbacks. For example, they are often considered unwieldy and expensive to construct.
Also, traditionally, pontoon logs included a generally hollow enclosure, with the air entrapped in the hollow enclosure providing the requisite buoyancy to maintain the structure afloat. In order to provide increased structural integrity to the material forming the hollow enclosure, billets of polystyrene foam have been inserted in the hollow enclosure in a generally T-shaped configuration extending the length of the pontoon log. The billets of polystyrene foam are buoyant and therefore provide some degree of floating in the event of a puncture of the material forming the hollow enclosure of the pontoon logs.
The polystyrene billets however do not prevent water from flooding the log interior through the puncture opening. The flooding of the interior of the pontoon log displaces the air therein and thereby significantly reduces the buoyancy of the pontoon log.
In order to reduce the influx of water into the pontoon log in the event it is punctured, the pontoon log may optionally be completely filled with floatation foam. While this construction provides the desired protection against influx of water into the pontoon interior in the event of a puncture, it may nevertheless suffers from several shortcomings. For example, when the foam is injected into the enclosure, the quantity of floatation foam required to completely fill the pontoon log interior adds considerable expense to the pontoon logs. Furthermore, some precautions are required to ensure the injected foam does not generate too much heat that could affect the integrity of the shell.
Indeed, a conventional method of manufacturing pontoons requiring closed-cell foam for positive buoyancy involves first manufacturing a generally parallelepiped-shaped rigid and hollow shell from a suitable polymeric resin such as high density polyethylene. The hollow shell is then filled with a closed-cell core by injecting a suitable polymeric resin such as expanded polystyrene foam thereinto. This method is both expensive and time consuming.
Furthermore, this prior art method makes it difficult to customize the amount of closed-cell foam within the shell depending on the desired buoyancy characteristics of the pontoon. Also, the prior art method makes it difficult to use existing components such as existing shell extrusions and existing core extrusions.
Other problems associated with prior art pontoons include a difficulty in assembling pontoons together or to decking structures. Also, prior art pontoons are particularly difficult to drag upon a solid surface, such as is often required when the pontoon is being dragged into or out of a body of water.
Furthermore, most prior art pontoons suffer from a lack of versatility in that they fail to provide a means for allowing the adjustment of the buoyancy and, hence, of the height of the structure they support relative to the body of water. Also, most prior art pontoons suffer from being unable to provide for stability-increasing features such as a balancing system.